Transmission Identification

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SASKCHEYENNE75

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C10
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350 4bbl
I picked up a scrap truck for a few parts and this transmission was in the back. Can someone help me by telling me what it is? I'm thinking a th350 but I'm not positive.
 

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PrairieDrifter

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350, 350, 350, 350, 350, 350
That may not be a Chevy. Let's see the pan.
 

85K304SPD

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Looks like a TH350. We need to see the pan shape.
 

legopnuematic

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Dart Swinger, Sierra 10, C10 Cheyenne, C10 Big Ten, Silverado 10, Ram 2500
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225/6, 350 c.i., 350 c.i., 5.9l Cummins
Turbo 200?
 

Rickf

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It's not a BOP. I thought someplace on this website or GMT400's there is a guide for GM transmissions based on pan gasket shape.
 

75gmck25

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Northern Virginia
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Bruce
Truck Year
1975
Truck Model
K25 Camper Special TH350 NP203
Engine Size
5.7
The TH-200 is a 4 speed overdrive automatic, and it works well to replace the TH350 if you don’t go too crazy on the horsepower . It can be built for high HP, but won’t handle it stock.
 

legopnuematic

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Dart Swinger, Sierra 10, C10 Cheyenne, C10 Big Ten, Silverado 10, Ram 2500
Engine Size
225/6, 350 c.i., 350 c.i., 5.9l Cummins
The TH-200 is a 4 speed overdrive automatic, and it works well to replace the TH350 if you don’t go too crazy on the horsepower . It can be built for high HP, but won’t handle it stock.
That's the 200-4R that's a 4speed overdrive, the 200 is a light duty 3 speed unit.
 

ButchM

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Its a TH200. The CY code puts it between about 1976 and 1981. Def a Chev bell housing.
Not a boat anchor necessarily. The best bet for this, IMHO, is to look for it a home with a circle track or drag racing group. These are popular with some of them due to the light rotating mass... like a Powerglide with an extra gear and they've been outta production for 35 yrs or so.
 

racprops

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I loved a 200R4, the have a lower first gear than a 700R4 and a taller Overdrive ratio:

200R4 ;

  • 1st gear: 2.74
  • 2nd gear: 1.57
  • 3rd gear: 1
  • 4th gear: .67
Gear Ratios:

  • First:3.059:1
  • Second:1.625:1
  • Third:1.00:1
  • Fourth:0.069:1
And in many cases it can directly swap in place of a TH350 like I did in a 79 Camaro.

Rich
 

Ricko1966

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kansas
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Rick
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1975
Truck Model
c20
Engine Size
350
I loved a 200R4, the have a lower first gear than a 700R4 and a taller Overdrive ratio:

200R4 ;

  • 1st gear: 2.74
  • 2nd gear: 1.57
  • 3rd gear: 1
  • 4th gear: .67
Gear Ratios:

  • First:3.059:1
  • Second:1.625:1
  • Third:1.00:1
  • Fourth:0.069:1
And in many cases it can directly swap in place of a TH350 like I did in a 79 Camaro.

Rich
We aren't talking about a 200r4 we're talking about the old light duty turbo 200s that were used for a few years. Light duty 3 speed auto. And in gear ratio terminology 3.07 [700r4 1st gear) is lower than 200r4 2.74 1st gear) a 4.10 rear gear is lower than a 3.08 rear gear, a higher numbered gear is a lower gear, it is confusing but that's how it's been termed for 100 years,maybe longer
 
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